1. Field of the Invention
This invention relates in general to certain new and useful improvements in an intermodal freight container construction, and more particularly, freight container structures which are primarily formed of reinforced plastic composite materials and reinforced by metal structural members at connector regions and where the metal structural members are integrated with the composite members.
2. Brief Description of the Prior Art
Intermodal transport containers for the shipping of freight are well known and have been widely used for a substantial period of time. These intermodal containers are highly effective where the cargo is designed for intercontinental shipment. Products of more sophisticated technology such as automobiles, television sets, etc., are frequently made in certain countries and transported to markets in other countries which do not have the technology or facilities to produce same.
Products for intercountry shipment are usually loaded into an intermodal freight container at a site of manufacture and shipped to a seaport by rail transportation. The intermodal freight container is thereafter loaded into an ocean-going ship for transport between continents. Upon arrival at the destination continent, the intermodal freight container is then removed from the ship and loaded onto a railroad transport car for delivery to a particular city where the container can then be loaded onto a truck transport for delivery to a particular site of use.
Very recently, there have been several proposals to provide intermodal vehicle haulers for the transport of automobiles. However, these proposed intermodal vehicle haulers were all to be primarily formed of metals such as aluminum or steel or combinations thereof. There have also been several vehicle haulers employed by railroad companies for the transport of vehicles but these vehicle haulers are all constructed from aluminum and steel combinations.
There are numerous problems which arise in the shipping of automobiles or other freight which is environmentally sensitive and subject to environmental damage in metal containers. Accordingly, there has been a need for a container which is made of non-metal materials as for example, a reinforced plastic composite material
The prior art is replete with metal containers having connector regions for removable connection to both freight container transports, such as flat bed trucks and flat bed railroad cars, and to other intermodal freight containers. Exemplary of these freight containers are those described and illustrated in U.S. Pat. No. 4,819,280 dated Apr. 11, 1989 to Weiner. This Weiner Patent discloses a lockable cargo container having elongate beams with connectors at the ends of the containers. The entire structure of the Weiner Patent is made of a metal, presumably aluminum and other metal combinations.
U.S. Pat. No. 3,456,829, dated Jul. 22, 1969 to Glassmeyer also discloses a container frame structure including a longitudinal metal beam and corner locking portions for intermodal container stacking. However, and again, the Glassmeyer frame structure is entirely formed of metal materials. U.S. Pat. No. 4,341,495 to Del'Acqua also discloses corner stackable containers having lockable corner posts. A locking member is capable of being received at each of these corner posts.
U.S. Pat. No. 3,801,177, dated Apr. 2, 1974 to Fylling et al also discloses reinforcing V-shaped torsion box beams. Fylling et al describe their shipping container as being frameless, although the container nevertheless includes several beams such as torsion beams which support articles in tiers and also distribute loading forces. U.S. Pat. No. 3,815,517, dated Jun. 11, 1974 to Przybylinski discloses a structure similar to that in the Fylling et al patent. However, the container in the Przybylinski Patent is designed for the transporting of automobiles. Przybylinski does employ longitudinally extending braces.
Each of the prior art intermodal containers heretofore described were all essentially constructed of metal. There have also been several proposed intermodal vehicle haulers for the transporting of automobiles but again, all such proposed haulers are to be formed of metals as aforesaid. This presents numerous problems, such as corrosion problems, unsealed interiors, substantial weight, and the like.
One of the major considerations in producing reinforced plastic composite intermodal freight containers is the fact that they must be light in weight, and preferably lighter in weight than a corresponding metal freight container. Furthermore, they must be capable of being environmentally sealed so as to protect the contents from salt water spray during ocean transit and from other environmental contaminants which can enter the container and possibly damage the contents.
It is also desirable to provide a connector system which permits interlocking of stacked intermodal freight containers without a gap between two stacked intermodal containers and which would improve the load distribution efficiency and reduce the overall height. Further, it would be desirable to have an intermodal freight container constructed substantially of reinforced plastic composite materials and which is light in weight but which has sufficient strength to withstand compressive and bending loads imposed on the container.